Foundry aerating flask-filler



March 19, 1963 G. M. BUTZOW FOUNDRY AERATING FLASK-FILLER 5 Sheets-Sheet1 Filed July 3, 1959 INVENTOR. GEORGE M. BUTZOW BY 1M I M ATTORNEYSMarch 19, 1963 G- M. BUTZQW 3,081,505

FOUNDRY AERATING FLASK-FILLER Filed July 3, 1959 s Sheets-Sheet 2' 1NVEN TOR. GEORGE M. BUTZOW ATTORNEYS March 19, 1963 G. M. BUTZOW3,081,505

FOUNDRY AERATING FLASK-FILLER Filed July 5, 1959 3 Sheets-Sheet 3INVENTOR. GEORGE M. BUTZOW ATTORNEYS United States Patent Ofiice3,0815%. Patented Mar. 19, 1963 3,081,505 FOUNDRY AERATING FLASK-FILLERGeorge M. Butzow, 4821 S. Wayne Ave., Fort Wayne, Ind. Filed July 3,1959, Ser. No. 824,856 3 Claims. (Cl. 22-35) The present inventionrelates to a foundry aerating flask-filler, and more particularly to amachine adapted to treat foundry molding green sand as it is beingintroduced into the flask, said treatment imparting to the sand aquality that enables it to form a superior mold as it is compressedagainst the pattern.

In the proper formation of a sand mold, it is necessary that the sand betreated properly and thereafter introduced into the mold box or flaskduring the moldforming operation. As a part of this treatment, it isdesirable that the sand be fluifed or aerated to render it substantiallyfluid and flowable and further to break up and eliminate all lumps orclods of compacted sand which may form. After the sand is properlytreated and it is desired to form a mold, the sand is sometimes siftedinto the mold box or flask containing the pattern. After the siftingoperation is completed and the flask is fllled to the proper level withsand, the sand is compacted to form the mold and the pattern is removed,leaving a mold cavity.

It is an object of this invention to provide a unique flask-fillingdevice for use in foundries, which is substantially automatic inoperation,is efficient in use, and is quite simple in construction.

It is still another object of this invention to provide a riddle machinefor use in foundries which is operable substantially automatically tofirst aerate the sand and then immediately after to sift or riddle thesand into a mold box for the forming of a mold.

Other objects will become apparent as the description proceeds.

To the accomplishment of the above and related objects, my invention maybe embodied in the forms illustrated in the accompanying drawings,attention being called to the fact, however, that the drawings areillustrative only, and that specific change may be made in the specificconstructions illustrated and described, so long as the scope of theappended claims is not violated.

In the drawings:

FIG. 1 is a longitudinal sectional illustration of one embodiment ofthis invention;

FIG. 2 is a side elevation thereof;

FIG. 3 is a front elevation;

FIG. 4 is a top plan View;

FIG. 5 is an enlarged fragmentary illustration of the eccentric weightsused on the aerator shaft; and

FIG. 6 is a fragmentary sectional illustration taken substantially alongsection line 66 of FIG. 1.

Referring to the drawings, the machine includes a stationary frameindicated generally by the reference numeral '1 formed for the most partof structural steel. The frame is box-like in shape, having an openinterior in which is disposed a housing 12 of sheet steel or the likewhich is closed on all sides but open at the upper and lower ends. inthe upper end portion of the housing 12 is a hopper, indicated generallyby the reference numeral '14, this hopper having an inclined floor 16and upstanding sides whichserve to guide sand into the hopper as it isfed through the mouth 18 thereof. Depending from the upper portion ofthis stationary frame 10 is a peripheral rim or flange 20 which extendsinside the side walls of the hopper 14. To seal against the leakage oroverflow of sand from the hopper, a flexible wall 22 formed ofcomposition rubber belting or some similar suitably strong, flexiblematerial is fastened to one portion of the flange 2t) and extendeddownwardly into firm engagement with the hopper floor 16, as shown inFIG. 1. This provides an eflective seal against sand leaking out of thehopper.

The hopper is provided with a relatively large discharge openingextending from the lowermost edge 24 of the hopper floor 16 to a point26 located upwardly and away from the point 24. It will be noted from anexami nation of the drawings that this opening 24, 26 is quite large, soas to accommodate the relatively free flow of large quantities of sandcontained in the hopper.

A valve or gate, indicated generally by the reference numeral 28, ismovable to close and open the hopper opening 24, 26, as may be desired.This gate 28 in the illustrated embodiment is formed of an arcuatelyshaped piece of sheet steel (FIG. 6) which is reinforced along thelateral edges by suitable flanges 30, as shown more clearly in FIGS. 1and 6.

Secured to the two flanges 30 are two arcuately shaped strips 32 ofrubber or steel which project above the plate 23 far enough to enter,respectively, two arcuately shaped channels 34 which are mounted on theunderside of the hopper 14- adjacent to the opening 24, 26. Thesechannels 3,4 may be formed of strip steel suitably edge-welded to thehopper floor.

As shown more clearly in FIG. 1, a strip 36 of resilient, rubber-likematerial is clamped to the underside of the hopper floor 16 so as toproject downwardly and beyond the point 24 of the hopper opening. Thisstrip 36 is positioned to be engaged by the distal or inner end 38 ofthe gate 28 so as to provide a tight seal or closure against sandescaping from the hopper when the gate is closed. I The hopper isfurther sealed by means of another strip 40 of resilient materialmounted on the depending flange 20 so as to slideably engage the uppersurface of the gate 28. The two strips 22 and 40 may be made of the samematerial.

The arcuate shape of the gate 28 corresponds to the arc of a circlehaving a center at 4-2 which is the axis of horizontal shaft 44journaled in suitable bearings 46 mounted on the stationary frame 10.Two suitable angle irons 48 secured to the shaft 44 are connected to thegate 28 whereupon the gate may be swung into and out of closed position,as may be desired.

The operation of the gate is preferably accomplished by means of apneumatic cylinder 56 (FIG. 2) having a connection at its left-hand endto the frame 10 and at its right-hand end to an arm 52 which is securedto the shaft 44. Actuation of the cylinder 50 thereupon serves to swingthe gate 28 either to the open or closed position, depending upon theoperation desired.

The housing '12 is held in position inside the frame 10 by means ofsuitable shock or vibration mounts 54 which in the present instance arefabricated of relatively soft but strong rubber as blocks, these blocks54 being mounted between angle irons 56 on the housing and suitablebrackets 58 on the stationary frame 10. By means of this type mounting,the housing 12 is free to vibrate with respect to the stationary frame10. Since the hopper '14 is actually a part of the housing 12, it thusbecomes immediately apparent that in order to close properly the hopperdischarge port 24, 26, some type of flexible or resilient seals such as22, 36 and 40 are needed. This is true because the gate 28 isstationary, being fixed to the frame .10, while the hopper itself isfree to vibrate with respect to the frame 10. Preferably, seals like 22and 4%] are used on the remaining two opposite sides of the hopper,these seals depending from flange Zil.

A baflle plate or inclined deflector 60 is welded or otherwise suitablyfastened to the inner wall of the housing 12 so as to lie in theposition illustrated in FIG. 1; this position is opposite the hopperdischarge port 24, 26.

Immediately beneath the hopper, and more particularly beneath the hopperport 24, 26, is located an aerator 62 (FIGS. 1 and 3). This aerator maybe of conventional construction, in the illustrated embodiment includinga plurality of rigid fingers 64 set at right angles with respect to eachother and arranged in spaced, side-by-side relation, as shown in FIG. 3.These fingers 64, for example, may be formed of steel and have athickness of one-eighth (Ms) inch and a width of one (1) inch; thelength may vary, depending upon specific design requirements.

These fingers 64 are clamped by some suitable means onto a shaft 66which is journaled in oppositely disposed bearings 68 mounted in thesides 70 of the housing 12 (FIG. 3). Between the bearings 68 and theaerator 62, and on the opposite ends of the aerator, are mounted two.eccentric weights 72, these weights being clamped to'the aerating shaft66, as shown more clearly in FIG. 5. As the shaft 66 rotates, theweights 72 as well as the aerator 62 rotate therewith.

As seen in FIG. 3, the left-hand end of the aerating shaft 66 isconnected to a flexible shaft coupling 74 which in turn is coupled tothe output shaft 76 of an electric motor 78. The motor 78 is flexibly orshock mounted on a platform 80 rigidly fastened to the main frame 10.Operation of the motor serves to rotate the output shaft 76 and with itthe flexible coupling 74, shaft 66, eccentric weights 72 and the aerator62.

Across the open bottom end of the housing 12 is fastened a distributingscreen 82 of a desired mesh size. This screen 82 is set at an angle asshown in FIG. 1 and is located directly beneath the aerator 62.Immediately beneath the screen 82 is a guide chute 84 which serves toguide sand sifted through the screen 82 to a desired location. Dependingupon the size of the flask, the chute 84 may be omitted.

On the back side of the housing 12, or, in other words, on theright-hand side as viewed in FIG. 1, the portion of the housing adjacentthe screen 82 is cut away to provide an opening 86, and in communicationwith this is a discharge chute 88 which is an extension of the screen82. Particles which are too large to pass through the meshes of a screen82 will flow through the opening 86 and outwardly from the dischargechute 88.

In operation, the frame is mounted on a rigid, stationary support. Themouth 18 of the hopper 14 is placed in communication with a supply oftreated molding sand such that this supply maintains the hopper 14filled at all times. A molding box or flask which is to be filled withmolding sand is positioned beneath the screen 82 in readiness to receivesand.

At this stage, the actuator 50 is operated to swing the gate 28clockwise, as viewed in FIG. 1. As the gate opens, an electrical switch(not shown) is automatically actuated to energize motor "78. As the gatecontinues to open, the motor 78 turns the aerator and the eccentricweights 72 at rated speed. Because of the eccentricity of the weights72, the system is unbalanced, thereby causing the housing .12 tovibrate. This vibration is relative to the stationary frame 10 and alsothe motor 78; however, since the motor is coupled to the shaft 66through flexible coupling 74 and is itself flexibly mounted on platform80,

the radial or eccentric .vibration of the shaft 66 will be accommodated.

As the gate opens and the housing vibrates, sand flows from hopper 14downwardly onto the 'bafiie plate 60 and onto the aerator 62. Theaerator 62 revolves at a high rate of speed and cuts or knifes throughthe gravitating sand, thereby flufling and aerating the latter. Thisfluffing action renders the sand more fluid and, further, breaks up anylumps or clods which may have already compacted, the sand which reachesthe screen 82 being of fine grain constituency and freely flowablethrough the screen. Any foreign particles or fragments which cannot passthrough the screen 82 will gravitate through the opening 86 and out ofthe discharge chute 88.

Since the housing 12 is constantly vibrating, the sand will freely flowthrough the sifting screen 82 and downwardly into the mold box.

In the working embodiment of this invention, a vibratory excursion ofthe housing 12 relative to the stationary frame 10 is only one-sixteenthto one-fourth A) of an inch, thereby making it possible to obtainextreme accuracy in producing a well-defined flow of sand from the sieve82 into a mold box (not shown). Thus, sand sifted from the machine maybe limited almost to the precise confines of the mold box and therebynot wasted. When it is considered that the sand is reused many times andthat the sand must be treated between each usage, this elimination ofwastage means considerable savings in the cost of foundry operation.

When a mold box has been filled with sand and it is desired to terminatethe sifting operation, the cylinder 50' is oppositely actuated forclosing the gate 28. The motor 78 is provided with a brake 79 such thatde-energization of the motor 78 results in almost instantaneous stoppingof the vibrating action as well as the rotary motion of the aerator 62.Once the gate '28 is completely closed, further flow of sand from thehopper 14 is prevented.

The use of the gate 28 provides a means for accurately controlling theflow of sand from the hopper to the mold box. Furthermore, this accuratecontrol coupled with the aerating function of the aerator 62 whichfurther treats the sand and converts it into a fluid-like constituencyproduces an even and free flow of sand through the screen 82. This leadsto an even distribution of compactable sand into the mold box.

While reducing wastage to a minimum, the machine is capable of operatingfaster than the usual manual operation, thereby providing another savingin cost of mold production.

Since the sand which emanates from the screen 82 is substantially fluidand freely flowable, its compression into a uniformly hard mold isgreatly facilitated.

In the proper formation of a green sand mold, it is necessary that thesurfaces of the mold, after the pattern has been withdrawn, be of equalhardness so that when the mold cavity is filled with molten metal itwill uni.- formly resist the pressure of the metal, thus producing acasting that is true to the pattern. This is most difficult to attainwhen the pattern has large flat areas, deep pockets and deep verticalsurfaces. Molding machines which squeeze or jolt (or both) the sandagainst the pattern are more or less successful in attaining a goodmold, depending upon the quality of the sand, its moisture content,strength, toughness and flowability. The present invention improves theflowability or fluid-like quality of the sand as it rests in the flaskjust before it is subjected to jolting and/ or squeezing.

In the past and current practice, a device called a riddle is frequentlyused to impart fiowability. These consist primarily of a screen bottomedbox through which the sand is sifted and sprinkled over the pattern.Riddles are shaken either by hand or by machine. In either case, it is atime-consuming operation, because the device must be separately filledand must use a relatively fine screen mesh to accomplish its purpose.Because of this, it has been too costly to introduce more than a thinlayer .of riddled sand over the pattern. Then, when the bulk of sand isintroduced by other means, such as a hand shovel or from an overheadchute, the heavy bulk of the added sand tends to pack the previouslyriddled sand, thus reducing its flowability and to that extentnullifying its benefits.

This invention renders it economically practical to fill the entireflask with a uniformly fiuffed, flowable sand of minimum density. Suchsand, when jolted and squeezed, will give the mostuniforrn mold surfacehardness, and will eliminate such casting defects as swells, rat-tailsand ram-offs when these are due to lumpiness and poor flowability of thesand.

The screen shown in this invention is relatively coarse in mesh and issloped to spread the sand evenly in the mold, rather than to sift orriddle the sand in the old sense. The flufling is done by the aeratorblades, the mesh being employed to distribute the flufied sand into themold flask evenly so it will be of uniform height in the flask prior tocompressing.

If the device were mounted on the discharge end of a belt conveyor whichsupplied it with sand and if the conveyor were mounted on arms so thatit could move horizontally in any direction, the screen cloth would notbe needed. It is needed only when the machine supporting frame isimmovable with respect to the mold flask.

It is common practice in foundries to fluff or aerate the sand as afinal step in the preparation process. However, much or almost all ofthis beneficial Working is lost before the sand can be placed into theflask; bucket elevators, diverting plows mounted over belt conveyors,the long fall from the conveyor to the bin and the drop from the bin tothe mold pattern all increase the density of the sand and to that extentnullify the benefits which could be obtained if it were possible tomaintain the sand in its aerated condition until it is finallycompressed in the mold. By making it practical to aerate the sanddirectly into the flask as it is being filled, this invention makes itpossible to preserve the beneficial effects of aeration to producebetter molds and better castings.

Also, since the old time-consuming practice of riddling or sifting iseliminated, lower mold production costs are achieved. Where it isdesired to remove impurities such as sand pills or small matterdetrimental to the casting process, a fine screen may be employed andthe material removed is conveyed away from the mold flask.

What is claimed is:

:1. A flask-filling apparatus comprising a stationary supporting frameof box-like configuration, a housing having closed sides and open ends,said housing being disposed inside said frame with said ends verticallyseparated, a plurality of resilient cushion supports mounting saidhousing inside said frame, a hopper secured in the upper portion of saidhousing in registry with the adjacent open end, said hopper having aninclined floor and a discharge opening which extends away from thelowermost portion of said floor upwardly toward the mouth of saidhopper, said opening lying in a plane that is inclined, said hopperhaving on the underside thereof two channels spaced apart and parallelon opposite sides of said opening, an arcuately shaped plate movable toclose said opening, said plate having two side flanges disposed to movein said two channels respectively, a flexible seal in strip form mountedon said stationary frame and extending into said hopper to engage theupper side of said plate to prevent leakage of sand, a flexible seal onthe bottom of said hopper and engageable with the lower end edge of saidplate to further seal said opening when said plate is closed, ahorizontally extending pivot shaft mounted on the outer side of saidsupporting frame, structure connecting said shaft to said plate forswinging the latter relative to said frame to open and close selectivelysaid hopper opening, an actuator on said frame and connected to saidplate for operating the latter, an aerator disposed inside said housingin'a position beneath said hopper opening, said aerator comprising aplurality of relatively thin outwardly extending rigid fingers mountedon a horizontal shaft in spaced side-by-side relation, said shaft havingopposite ends journaled in the sides of said housing, two eccentricweights secured to the opposite end portions of said aerator shaft, amounting platform rigidly secured to said supporting frame, a motormounted on said platform, a flexible coupling connecting said aeratorshaft to said motor whereby rotation imparted to said aerator shaft bysaid motor rotates said eccentric weights for vibrating said housing, adistributing screen over the lower open end of said housing, said screenbeing inclined, and a dischage opening in the bottom of said housingadjacent to the lowermost edge of said screen for discharging particlestoo large to pass through said screen.

2. A flask-filling apparatus comprising a stationary sup porting frameof box-like configuration, a housing having closed sides and open ends,said housing being disposed inside said frame with said ends verticallyseparated, a plurality of resilient cushion supports mounting saidhousing inside said frame, a hopper in the upper portion of said housingin registry with the adjacent open end, said hopper having an inclinedfloor and a discharge opening which extends away from the lowermostportion of said floor upwardly toward the mouth of said hopper, saidopening lying in a plane that is inclined, said hopper having on theunderside thereof two channels spaced apart and parallel on oppositesides of said opening, an arcuately shaped plate movable to close saidopening, said plate having two side flanges disposed to move in said twochannels respectively, a flexible seal in strip form mounted on saidstationary frame and extending into said hopper to engage the upper sideof said plate to prevent leakage of sand, a flexible seal on the bottomof said hopper and engageable with the lower end edge of said plate tofurther seal said opening when said plate is closed, a horizontallyextending pivot shaft mounted on the outer side of said supportingframe, structure connecting said shaft to said plate for swinging thelatter relative to said frame to open and close selectively said hopperopening, an actuator on said frame and connected to said plate foroperating the latter, an aerator disposed inside said housing in aposition beneath said hopper opening, said aerator comprising aplurality of outwardly extending rigid fingers mounted on a horizontalshaft having opposite ends journaled in the sides of said housing, twoeccentric weights secured to the opposite end portions of said. aeratorshaft, a mounting platform rigidly secured to said supporting frame, amotor mounted on said platform, a flexible coupling connecting saidaerator shaft to said motor whereby rotation imparted to said aeratorshaft by said motor rota-tes said eccentric weights for vibrating saidhousing, and a distributing screen over the lower open end of saidhousing.

3. A flash-filling apparatus comprising a stationary supporting frame ofbox-like configuration, a housing having closed sides and open ends,said housing being disposed inside said frame with said ends verticallyseparated, a plurality of resilient cushion supports mounting saidhousing inside said frame, a hopper in the upper portion of said housingin registry with the adjacent open end, said hopper having an inclinedfloor and a discharge opening which extends away from the lowermostportion of said floor upwardly toward the mouth of said hopper, saidopening lying in a plane that is inclined, said hopper having on theunderside thereof two channels spaced apart and parallel on oppositesides of said opening, an arcuately shaped plate movable to close saidopening, said plate having two side flanges disposed to move in said twochannels respectively, a flexible seal in strip form mounted on saidstationary frame and extending into said hopper to engage the upper sideof said plate to prevent leakage of sand, a flexible seal on the bottomof said hopper and engageable with the lower end edge of said plate tofurther seal said opening when said plate is closed, a horizontallyextending pivot shaft mounted on the outer side of said supportingframe, structure connecting said shaft to said plate for swinging thelatter relative to said frame to open and close selectively said hopperopening, an actuator on said frame and connected to said plate foroperating the latter, an aerator disposed inside said housing in aposition beneath said hopper opening, said aerator comprising aplurality of outwardly extending rigid fingers mounted on a horizontalrotatable shaft having opposite ends journaled in the sides of saidhousing, and two eccentric weights secured to the opposite end portionsof said aerator shaft.

(References on following page) References Cited in the file of thispatent UNITED STATES PATENTS 1,772,874 Meyer Aug. 12, 1930 1,962,734Dupre June 12, 1934 2,171,115 Kiesskalt et a1 Aug. 29, 1939 2,412,425Rawson Dec. 10, 1946 8 Erisman Oct. 26, 1948 John Nov. 19, 1957 FOREIGNPATENTS Germany Nov. 28, 1930 Germany Sept. 10, 1931 Great Britain I an.24, 1951

1. A FLASK-FILLING APPARATUS COMPRISING A STATIONARY SUPPORTING FRAME OFBOX-LIKE CONFIGURATION, A HOUSING HAVING CLOSED SIDES AND OPEN ENDS,SAID HOUSING BEING DISPOSED INSIDE SAID FRAME WITH SAID ENDS VERTICALLYSEPARATED, A PLURALITY OF RESILIENT CUSHION SUPPORTS MOUNTING SAIDHOUSING INSIDE SAID FRAME, A HOPPER SECURED IN THE UPPER PORTION OF SAIDHOUSING IN REGISTRY WITH THE ADJACENT OPEN END, SAID HOPPER HAVING ANINCLINED FLOOR AND A DISCHARGE OPENING WHICH EXTENDS AWAY FROM THELOWERMOST PORTION OF SAID FLOOR UPWARDLY TOWARD THE MOUTH OF SAIDHOPPER, SAID OPENING LYING IN A PLANE THAT IS INCLINED, SAID HOPPERHAVING ON THE UNDERSIDE THEREOF TWO CHANNELS SPACED APART AND PARALLELON OPPOSITE SIDES OF SAID OPENING, AN ARCUATELY SHAPED PLATE MOVABLE TOCLOSE SAID OPENING, SAID PLATE HAVING TWO SIDE FLANGES DISPOSED TO MOVEIN SAID TWO CHANNELS RESPECTIVELY, A FLEXIBLE SEAL IN STRIP FORM MOUNTEDON SAID STATIONARY FRAME AND EXTENDING INTO SAID HOPPER TO ENGAGE THEUPPER SIDE OF SAID PLATE TO PREVENT LEAKAGE OF SAND, A FLEXIBLE SEAL ONTHE BOTTOM OF SAID HOPPER AND ENGAGEABLE WITH THE LOWER END EDGE OF SAIDPLATE TO FURTHER SEAL SAID OPENING WHEN SAID PLATE IS CLOSED, AHORIZONTALLY EXTENDING PIVOT SHAFT MOUNTED ON